Hypoglycemic activity of the antioxidant saponarin, characterized as alpha-glucosidase inhibitor present in Tinospora cordifolia.
Tinospora cordifolia, used in anti-diabetic herbal drug preparations, was reported [12] to contain an alpha-glucosidase inhibitor, characterized as saponarin (apigenin-6-C-glucosyl-7-O-glucoside). The leaf extract had appreciable antioxidant and hydroxyl radical scavenging activities and contained the flavonoid in the range of 32.1 +/- 1.5-45.5 +/- 3.5 mg/g of dry solid. Saponarin showed mixed competitive inhibition on activities of alpha-glucosidase and sucrase of different origins. IC(50), Ki and ki' values determined were 48 muM, 8 muM and 19.5 microM respectively for intestinal maltase and 35 microM, 6 microM and 13 microM respectively for intestinal sucrase. When given orally to maltose-fed rat, saponarin showed hypoglycemic activity in the range of 20-80 mg/kg compared to 100-200 mg/kg for acarbose as reported.
Sengupta
Subhabrata
S
Department of Biotechnology, Heritage Institute Technology, Calcutta, 700107, India. profs_sengupta@yahoo.ca
Mukherjee
Abhishek
A
Goswami
Riddhi
R
Basu
Srabanti
S
D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D047310:Apigenin / Q000737:chemistry / Q000494:pharmacology*; D001667:Binding, Competitive; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000378:metabolism; D005960:Glucosides / Q000737:chemistry / Q000494:pharmacology*; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D007700:Kinetics; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D013393:Sucrase / Q000037:antagonists & inhibitors / Q000378:metabolism; D031610:Tinospora / Q000737:chemistry* / Q000378:metabolism; D000520:alpha-Glucosidases / Q000378:metabolism
D000975:Antioxidants; D004791:Enzyme Inhibitors; D016166:Free Radical Scavengers; D005960:Glucosides; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D010936:Plant Extracts; C457771:saponarin; D047310:Apigenin; D000520:alpha-Glucosidases; D013393:Sucrase